Arrangement of connections for sending and receiving electric waves



March 29, 1927. I 1,622,679

C. SCHWARZ ARRANGEMENT 0F CONNECTIONS FOR SENDING AND RECEIVING ELECTRICWAVES Filed Oct. 51. 192] Receiverx BY BQMLINVEZTW? Patented Mar. 29,1927.

UNITED STATES 1,622,679 PATENT j OFFICE.

cam. scnwanz; :oE cnan oTrEneune. NEAR "BERLIN, GERMANY, nssrenon roWESTINGHOUSE ELECTRIC & manuracrunme company, a conronarron orPENNSYLVANIA.

-ARRANGEMENT or conNEc'rIons r03. sEnnme AND nEcEIvINa- ELEcrnIc WAVES.

, a pncamnmea October 31, .1921, Serial'li'o. 511,831, and in GermanyMay 26, 1921.

This invention relatesto a systemlfor sending and receivingradiosignals, although paths and it inclu es'arrangements for securingproper balancing among-the paths. f

It is a further object of this invention to devise a system wherein thebalancing 111st mentioned may be used to prevent energyfrom the sendingapparatus fromactuating 15 the receiving apparatus at the same station.It is a-further object of this invention to provide for interchangingthe connections of the several paths so that greatexactness of balancingshall not be required.

Other objects and details of construction will be apparent from thefollowing descrip- 7 tion and the accompanying drawing, where- Figure 1is a.diagrammatic,illustration of one embodiment of mv invention.

Fig.2 is a similar illustration of another.

embodimentofmy invention. and I Fig. 3 is an illustration of themodification of-the form shown in Fig. 2.

In Fig. 1, 1, 2 and 3 represent three ans tennae. These may be ordinaryradiating antennae or they may be wires parallel to the line wires shownat 15, 16 and 17. These line wires may be a power-transmission line, 35the wires of an ordinary telephone line or or the'wires of ahigh-tension transmission line.

To each of the antennae is connected a tuned circuitincludingrespectively. the inductors' 4, 5 and 6. These inductors areioined together star-fashion and the center is connected to the ground.The outer end of each inductor is connected to its respective antenna.Adjustable condensers '7, 8 and 9, in parallel to each of the inductors,respectively, provide for the tuning.

The sending devlce indicated by the Ward Sender is of any desired form.It is not illustrated because the particular form of sending device usedis not related to the invention covered by this application. In the sameway, the receiving device is indicated by the word Receiver appearingadjacent in- Idicator 12. The sending device delivers its energy totwocoils 10 and 11 connected in series and in inductive relation,respectively, to the coils 4 and 5. The receiving device obtainsenergy-through the .coil 12 which is inductively related to the coil 6.The

coupling between the .coils 10 and 4 and the coupllng between the coils11 and 5 are so adjusted that the'point 14=becomes a potential node, sothat the electrical changes in the coils 4. and 5 do not effect the coil6. The energy sent out by-thesending device, therefore, is delivered tothe antennae 1 and to the wires 15 and 16 without afi'ecting thereceiving device. The tuning devices 7 and cures a perfect balance, itis possible to further adjust the balancing by altering theelectrostatic coupling between the wires 1 i and 15 or the wires 2 and16.

When" the balancing of the energy delivered bythe sending device issufficiently perfect so that it does not affect the receiving device atthe same station, there will still remain sufiicient unbalancing in theline wires 15, 16 and 17 so that a'distant station, although its sendingdevice be adjusted for balancing. will deliver unbalanced energy throughthe antennae 1 and 2. and the receiving device at the illustratedstation will be actuated thereby. The receiving device is also actuatedby energy received from the wire'17 through the antenna 3. It will beapparent that, even when the balancing is imperfect, the point 1 1 canbe made to act as a potential node, because it is connected to theground and is, therefore, kept at zero potential.

In Fig. 2, a similar system is illustrated.

At station A, the sending device is represented by S1 and the receivingdevice by R1. At station B, the sending device is represented bv S2 andthe receiving device by R2. The lines 15, 16 and 17' are connected tothe several inductors 4. 5 and 6'by capacities 18, 19 and 20. Thesecapacities may be pairs of parallel wires as already described inconnection with Fig. 1. but preferably they are formed by the insulatingsupports of the ,wires 15, 16 and 17'; for"exa1 nple,by

- connecting to metallic coatings upon opposite sides of the suspensioninsulators.

The effect of the balancing arrangement 1n Fig. 2 is, as alreadydescribed, that the sending device S1 delivers energy so divided betweenthe coils 4 and 5 at station A that the point 14 there remains atconstant potential. The coil Swill be undisturbed thereby and,therefore, the receiver R1 will not obtain current from the sendingdevice S1. The current sent out from the sending device S1 travels overthe wires 15 and 16 and reaches the point 14 at station B over the coils4 and 5 there, from this point it returns to station A over the coils 6and wire 17, reaching the point 14 at station A. Although thisdescription of the circuit seems to indicate a flow through the coils 6at each station, the eflect of the balancing described above shows thatthis current is theoretically zero. Adjustment at station A can producethis result at that station so that the energy sent out by the sendingdevice S1 will not afiect the receiver R1. There will, however, besufiicient unbalancing in the line so that the receiver R2 at station Bwill be affected. In the same way, adjustments at station B can be madeso that the sending device S2 will not affect the receiver R2 but willproduce an efiect at the receiver R1.

It will be obvious that thisarrahgement causes a very small current toflow in the wire 17 and that the energy received at the receivinginstruments is small. This disadvantage canbe avoided by interchangingthe connections, as illustrated in Fig. 3, where the corresponding partsare indicated by the samereference characters. The two inductors 5 areconnected at each station as in Fig. 2 but the connection from theinductor 4 at station A, instead of going to the inductor 4 at stationB, goes to the inductor 6, and the connection from inductor 6 at stationA goes to the inductor 4 at station .8. With thisarrangement, when abalance is obtained at station A, so that no energy is delivered fromthe sending device S1 to the receiver R1, a considerable proportion ofthe ener from the sending device SL will be received at the receivingdevice R2, since a direct path from the inductor 5 instation A over wire16, inductor 5 at station B, inductor 6 at station B and the return wireto the inductor 4 at station A exists, which receives the full potentialdiflerence at station A.

Proper balancing between the inductors 5 and 6 atstat-ion B is, in thisform, correlated with the balancing b'etween inductors 4 and 5 atstation A. This leaves the balance between inductors 4 and 5 at stationB available for the operator there so that he' can vention is capable ofmany applications. It is alsoobvious that many variations in the detailsof construction may be made without departing from the spirit of thisinvention, I therefore, do not intend the patent to be limited except asnecessitated by the prior art or indicated by the claims.

I claim as my 1nvention:

1. In a signaling system, three line wires connecting two stations, aconnection at the first of said stations between the first and secondofsaid line wires, means for impress ing signaling energy upon saidconnection, said means being balanced, whereby a poten tial node will bepresent in said connection, a connection between said potential node and1 the third wire, a signal-receiving device in said last namedconnection, a connection at the second station between the first andthird of said wires, means for impressing signal ing energy upon saidconnection,"said means being balanced, whereby a potential node will beproduced in said connection and a connection between said potentialvnode and the second of said wires, said connection including asignal-receiving device.

2. In a signaling-system, three line wires connecting two stations, aconnection at the first'of. said stations between the first and secondof said line wires, means for impress ing signaling energy uponsaidconnection, said means being balanced, whereby a potential node will bepresent in said connection, a connection between said potential node andthe third wire, a signal-receiving device in said last named connection,a connection at the second station between the first and third of saidwires, means for impressing signal ing energy upon said connection, saidmeans gy whereby the signal-sending energy at each station is preventedfrom effecting the reoeiving device at that station.

3. In a three-wire signaling line, a bridge across two of said wires, abridge between one of said two wires and the third wire, a connectionbetween said third'wire and the neutral point of said first namedbridge, a connection between the neutral point of the second namedbridge and the remaining one of said two wires, signal-receiving devicesin the said connections to the neutral points and means for impressingsignal-sending energy upon said bridges.

4. In a signaling system, two stations, a sending device and a receivingdevice at each station, a line including a plurality of conductorsbetween said stations, means for establishin a balanced relation at eachsta- -conductors, whereby the balancing means at tion where y thesignals sent by the sending one station will not revent the sendingdevice at that station will be without efiect -means there from a ectingthe receiving 10 on the receiving device at the same station, device atthe other station.

5 and one of the conductors being so arranged In testimony whereof Iaflix my signature.-

that signaling frequency energy is attenu- 4 ated more therein than incertain of the other CARL SCHWARZ.

